Big commit.

server: Replaced promises implementation with await/defer from IcedCoffeeScript.
server: Added patch for ICS to output valid filenames in generated JS.
server: Changed XML and feed parsers to work with streams instead of strings.
server: Implemented /summary, removed the index handler and moved www/* under /.
server: client: Use encodeURIComponent/decodeURIComponent for feed URLs
client: Refactored view code out of controllers.coffee and merged helpers.coffee into it.
server: Enhanced XmlParser to not maintain the entire parsed document in memory.